The yellow alert for flight delays at airports in Shanghai and Hangzhou has been lifted as weather in the region cleared up, the mainland’s civilian air traffic authority said in an update on its website.

The Civil Aviation Administration of China’s Air Traffic Management Bureau said all operations at Shanghai’s Pudong and Hongqiao international airports as well as Hangzhou’s Xiaoshan airport had returned to normal in the afternoon.

Some routes had also regained their usual levels of air traffic capacity, it said.

The Shanghai Airport Authority posted an update at 1.40pm on its official weibo account, stating that the cloudless weather was now suitable for both take-offs and landings. It added that no flight had been delayed for more than two hours today.

The aviation administration had warned last night that Shanghai’s two airports would face large-scale delays this afternoon because of large clusters of rain clouds that were expected to form above the city between 1pm and 5pm today.

The airports would suffer a 36 per cent fall in air traffic capacity, it said. It added that Hangzhou’s Xiaoshan airport would also be affected.

The bureau’s warning last night came on the back of reports of massive flight delays and cancellations across the mainland over the stormy weekend. Air traffic was severely disrupted amid thunderstorms that hit many regions.

As of 6pm yesterday, 55 flights had been cancelled and 126 delayed at the Beijing Capital International Airport. Shanghai’s two airports saw 130 flight cancellations and more than 500 delays.

Other major cities including Guangzhou, Shenzhen, Hangzhou, Haikou, Nanchang, Nanning, Xining and Lanzhou also experienced delays.

The airport in Xiamen, Fujian province, was the hardest hit, with the administration issuing its highest red alert for delays in the morning. One runway was closed for two hours and air traffic capacity dropped 77 per cent. The alert was lifted in the afternoon.

The Ministry of National Defence said yesterday that weather played a significant role in the air traffic disruptions and that they were not caused mainly by military drills. Military exercises were scheduled in the southeast coastal areas, but they would begin only tomorrow, it said.

The aviation administration said last week that delays at key airports in the east were the result of “stormy weather and regular military drills” and would last until August 15.

Analysts have estimated that military use of airspace in the country left as little as 20 per cent for civilian traffic.

The ministry has vowed to minimise the impact of the military drills on civil aviation by opening up temporary routes, giving some of its airspace to passenger flights and arranging detours in advance.